47—Rock outcrop-Rubble land complex, 60 to 90 percent slopes
Map Unit Setting
General location: Steep side slopes, mainly on the caldera rim
Major land resource area (MLRA): 3
Elevation: 6,000 to 8,000 feet
Average annual precipitation: 50 to 70 inches
Average annual air temperature: 38 to 42 degrees F
Frost-free period: 0 to 50 days
Map Unit Composition
Rock outcrop: 50 percent
Rubble land: 45 percent
Minor components: 5 percent
Characteristics of the Rock Outcrop
Landform: Stratovolcano
Geomorphic position: Rock outcroppings on side slopes of mountains and the caldera rim
Parent material: Andesite
Characteristics of the Rubble Land
Landform: Talus slope
Geomorphic position: Talus on side slopes of mountains and the caldera rim
Parent material: Colluvium derived from andesite
Characteristics of the Minor Components
Llaorock soils
Percentage of map unit: 5 percent
Landform: Stratovolcano
Geomorphic position: Side slopes of mountains and the caldera rim
Major Features and Properties Affecting Management
Rock outcrop
• Steep slopes
• Lack of soil material
Rubble land
• Steep and unstable slopes
• Rock fragments
• Lack of soil material
